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1.
通过与蓝莓上已报道的类拟盘致病菌系统发育对比,发现有5株类拟盘菌株聚集形成一个相对独立分支,表明这5株菌可能属于1个危害蓝莓的新纪录种;为确定该危害蓝莓的类拟盘多毛孢种类,采用三层次系统发育比较法和传统形态鉴定法对其进行鉴定,结果表明5株病原菌均属于Pestalotiopsis kenyana,分生孢子大小为(20.7~28.8)μm×(4.7~7.2)μm,中间三色细胞同色,长为13.2μm~18.0μm,具2~3根顶端附属丝,1根基部附属丝。  相似文献   

2.
摘 要：在澳洲坚果园进行病样采集时,发现一种叶部病害,为明确该病害的病原菌种类,将采集的病叶进行分离,并运用科赫法则测定致病性,根据病原菌的形态学特征和rDNA-ITS序列分析对病原菌进行鉴定。结果表明,分离菌株的菌落形态和分生孢子形态都与小孢拟盘多毛孢（Pestalotiopsis microspora）一致,经分子生物学鉴定,其ITS序列与小孢拟盘多毛孢的ITS序列的同源性为99%,将引起澳洲坚果叶斑病的病原菌鉴定为小孢拟盘多毛孢。生物学特性结果表明：PDA培养基最有利于病原菌生长,培养3天后,菌落直径达62.9 mm,最佳碳源为葡萄糖,最佳氮源为硫酸铵,病原菌在15-30 ℃均能生长,最适生长温度为28℃,病原菌在pH为4-11范围内均可生长,pH为7时生长最佳,全光照有利于病原菌生长。本文首次报道Pestalotiopsis microspora引起澳洲坚果叶斑病。  相似文献   

3.
2014年5月,在海南省乐东、东方、三亚等芒果主要产区,发现一种芒果生长期的新型果实病害,主要为害果实,对叶片、果柄等也有影响,严重影响海南芒果品质,制约芒果产业发展。为明确致病菌,以期为病害防治提供依据,保障芒果产业发展,观察其田间发病情况与症状,并依据科赫法则进行病原分离、培养和回接试验,结合病原菌生物学特性以及分子生物学鉴定。结果表明,该病害症状表现为芒果果实上产生圆形或近圆形表面开裂突起斑点,有时渗出透明的粘液,粘液流经斑点处出现黑色小点,严重时病斑合并呈不规则形,病斑未深入果肉。该菌培养菌落初期呈灰白色放射状圆形,后期产生黑褐色色素,菌丝变为黑色;培养皿背面颜色由蓝黑变为黑色。未成熟的孢子无色、单孢、近卵形,分生孢子大小为（1.7286~9.8785）μm?（1.5937~6.6502）μm;成熟的孢子暗褐色、双孢,分生孢子大小为（9.5235~14.4462）μm?（2.2137~6.1555）μm;分生孢子器扁圆形,产孢体褐色。将其rDNA-28S和rDNA-ITS序列经BLAST搜索比对,结合形态学观察,初步鉴定该病害的病原菌为Botryosphaeriaceae科Lasiodiplodia sp.。该病原菌致芒果生长期病害为国内首次报道。  相似文献   

4.
从华中农业大学草坪草的狗牙根Cynodon dactylon上分离得到引起该草坪草黑斑病的病原菌,并对该病原菌进行了形态学观察、致病性测定、rDNA-ITS序列分析以及生物学特性的研究.研究结果表明:该病原菌在PDA培养基上培养7 d后菌落呈墨绿色,菌丝有隔,分生孢子有3个隔膜,中间两细胞较大,弯曲,两端细胞颜色较浅.孢子平均大小为24.94 μm×10.30 μm.其rDNA-ITS序列表明,分离的病原菌与Genbank中的Curvularia verruculosa的同源性是99%,结合形态学特征和致病性测定认为该菌为C.verruculosa.生物学特性研究表明,该菌丝在pH值5.0～9.0的PDA上均能生长,最适碳源为可溶性淀粉,最适氮源为KNO3.菌丝生长的致死温度为70 ℃ 15 min,孢子萌发的致死温度为75 ℃ 15 min.这是C.verruculosa引起狗牙根黑斑病的首次报道.  相似文献   

5.
桑卷叶枯病是桑树的主要真菌病害之一。采用常规的微生物学试验方法观察病原菌桑单胞枝霉菌(Hormodendrummori Yendo)的形态并研究病原菌的分离培养条件。结果表明,病原菌在PDA培养基上生长良好,形成白色圆形凸状菌落,并能产生大量的暗蓝褐色分生孢子梗和淡灰色分生孢子;菌丝的生长温度为8～40℃,产生分生孢子的温度为10～38℃,分生孢子的致死温度为50～55℃,菌丝生长和分生孢子产生的最适温度为25～30℃;适合菌丝生长的pH为4.5～11.0,最适pH为6～7;相对湿度大有利于菌丝生长和分生孢子的产生与萌发;连续光照可促进产孢。以上结果信息可供研究桑卷叶枯病病原菌的危害特点和建立病害的有效防治方法参考。  相似文献   

6.
以高寒草地优势植物乳白香青(Anaphalis lactea)内生细菌RC14为研究对象,采用平板对峙法测定其对植物病原真菌的抑菌能力;并利用16S rDNA序列分析结合形态特征和生理生化特性对RC14进行鉴定。结果表明:RC14对多种植物根部病原菌和叶斑病菌均具有良好的抑制作用,抑制的病原菌种类有葡萄孢属(Botrytis)、蠕孢属(Bipolaris)、链格孢属(Alternaria)、镰孢菌属(Fusarium)和丝核菌属(Rhizoctonia)等植物病原真菌属,说明RC14具有较广的抑菌谱。RC14菌体杆状,大小为1.9~3.3 μm×0.7~0.8 μm, G+,中生芽孢,形态特征和生理生化特性及16S rDNA基因序列综合分析结果表明RC14为枯草芽孢杆菌(Bacillus subtilis)。本研究结果为开发和利用高寒草地所特有植物的内生拮抗菌提供了理论依据,为开发生物农药提供菌种资源。  相似文献   

7.
采用常规组织分离法,对甘肃省武威市紫花苜蓿根腐病菌进行分离和致病性测定,并通过形态学特征和分子鉴定方法对致病性最强的菌株进行鉴定。结果表明,MXGF7可造成紫花苜蓿严重根腐,该病原菌大型分生孢子多纺锤形或镰刀形,大小为3.3～4.7μm×14.8～32.0μm;小型分生孢子少,纺锤形或哑铃形,大小2.9～4.2μm×8.4～18.2μm;ITS序列及镰孢菌Fu3/Fu4区基因序列分析表明,病原菌均与Fusarium chlamydosporum的相似度达99%,结合形态学特征将该病原菌鉴定为厚垣镰孢菌F.chlamydosporum。采用平板对峙法,从分离自东祁连山高寒草地牧草的123株内生细菌中筛选出61株菌株对F.chlamydosporum有拮抗效果,且抑菌率均在55%,并利用形态特征和16SrDNA基因序列分析将具有稳定拮抗作用265ZY3菌株鉴定为解淀粉芽孢杆菌Bacillus amylolique　faciens。  相似文献   

8.
郑莉  黄俊斌  向培建 《草地学报》2006,14(4):315-318,327
从宜昌市夷陵区草坪型高羊茅(Festuca arundinacea.)分离出引起叶斑病的病原真菌,对该菌进行了形态学观察、致病性鉴定、核糖体DNA-ITS序列分析和生物学特性研究。结果表明:该病原菌能侵染高羊茅,在26℃和光照下,在PDA培养基上培养6d后菌落呈墨绿色,菌丝有隔,分生孢子有4个横隔膜,平均大小为30.6~17.0μm×10.9~13.6μm,中部3胞暗色,第3个细胞基部膨大;其核糖体DNA-ITS序列分析表明,该菌与GenBank中近缘弯孢(Curvularia affinis)的同源性是100%;结合形态学特征和致病性测定,认为该菌为C.affinis,这是C.affinis引起草坪型高羊茅叶斑病在我国的首次报道;生物学特性的研究表明,该菌菌丝生长的最适温度为25~30℃,最适pH范围为6~7,最适碳源为蔗糖,最适氮源为Ca(NO3)2;菌丝和分生孢子的致死温度分别为55℃10min和60℃10min。  相似文献   

9.
结合形态学与分子生物学分析,对采自重庆地区疑似由链格孢菌引起的枇杷叶斑病样品进行病原菌分离鉴定。结果表明,所得病原菌的rDNA-ITS序列与 GenBank中登陆的四株链格孢菌Alternaria alternate（登录号分别为：FJ228163、KT192329、KM100451、KP278185）的相似性均为99%,结合病原菌的菌落、分生孢子形态特征及致病性测定结果,将其鉴定为链格孢菌Alternaria alternate,GenBank登录号为KY397985,并命名为24-CQYB。室内毒力测定结果显示,咪鲜胺、嘧菌酯、甲基硫菌灵、多菌灵及苯醚甲环唑等5种杀菌剂对24-CQYB菌株生长均有抑制作用,其中苯醚甲环唑的抑制效果最好,EC50为3.84 mg/L。  相似文献   

10.
西藏秋播燕麦苗期褐斑病病原鉴定及生物学特性研究   总被引：3，自引：0，他引：3  
通过病原菌的分离、回接及病原菌形态学鉴定,将西藏秋播燕麦褐斑病的病原鉴定为麦根腐平脐蠕孢（Bipolaris sorokiniana）。病菌菌丝在5～35℃均可生长,最适生长温度30℃;在10～30℃均可产孢,20℃时的产孢量最大。培养温度不同,孢子大小亦不同,20℃时孢子最大;15℃时孢子隔膜数最多。分生孢子在10%...  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
Tropical Animal Health and Production -  相似文献   

14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

17.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

18.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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